As road traffic has continued to increase at rates greater than increases in road capacity, the effects of increasing traffic congestion have had growing deleterious effects on business and government operations and on personal well-being. Accordingly, efforts have been made to combat the increasing traffic congestion in various ways, such as by obtaining information about current traffic conditions and providing the information to individuals and organizations. Such current traffic condition information may be provided to interested parties in various ways (e.g., via frequent radio broadcasts, an Internet Web site that displays a map of a geographical area with color-coded information about current traffic congestion on some major roads in the geographical area, information sent to cellular telephones and other portable consumer devices, etc.).
One source for obtaining information about current traffic conditions includes observations supplied by humans (e.g., traffic helicopters that provide general information about traffic flow and accidents, reports from drivers via cellphones, etc.), while another source in some larger metropolitan areas is networks of traffic sensors capable of measuring traffic flow for various roads in the area (e.g., via sensors embedded in the road pavement). While human-supplied observations may provide some value in limited situations, such information is typically limited to only a few areas at a time and typically lacks sufficient detail to be of significant use. While traffic sensor networks can provide more detailed information about recent traffic conditions on some roads in some situations, various problems exist with respect to such information, as well as to information provided by other similar sources. For example, many roads do not have road sensors (e.g., geographic areas that do not have networks of road sensors and/or arterial roads that are not sufficiently large to have road sensors as part of a nearby network), and even roads that have road sensors may often not provide accurate data (e.g., sensors that are broken and do not provide any data or provide inaccurate data). Moreover, if information from such a road traffic network is not available in a timely manner (e.g., due to temporary transmission problems and/or inherent delays in providing road traffic network information), the value of such information is greatly diminished. Furthermore, some traffic-related information may be available only in raw and/or disaggregated form, and therefore may be of limited utility.
Thus, it is often difficult or impossible to obtain current and accurate information about road traffic conditions on roads of interest. Moreover, even if such current accurate road traffic conditions information is available, that information has only limited value in projecting what road traffic conditions will be like at a later time (e.g., 3 hours in the future, a week in the future, etc.), which may be of interest in various situations (e.g., to a person planning a later trip or beginning a trip now that will reach roads of interest at some point in the future, to a person coordinating multiple vehicles traveling over the roads at various times, etc.). For example, a multi-car accident that has currently halted traffic flow on a particular road may have little effect on traffic flow on that road later in the day or at the same time next week.